It is not uncommon for a document to contain a reference to relevant external content. Exemplary references, also referred to as links, include a reference citation, a URL to a website, an annotation to an external resource, a bibliographic entry and other indications of relevant external content. Accessing the external content referenced in a document may necessitate a user explicitly following a link or entering information into a search engine or performing other cumbersome processes which may render retrieval of the external content a tedious process. Methods and systems for automatic analysis of a document image to extract references to and to retrieve external content may be desirable.